1. Field of the Invention
The present invention relates to a workhead intended for metal working machines, which is adaptable for use in such mechanical working of metals and plastics involving the use of liquid lubricants and/or coolants. Hence, the term mechanical working encompasses various machining operations, such as turning, grindings etc. as well as non-cutting treatment of surfaces to be worked, such as for example the use of various pressing tools for finishing a surface. The invention relates also to a method for mechanical working of materials with a workhead, including a tool acting on a surface to be worked and means for supplying a liquid lubricant and/or coolant onto the working area of a surface to be treated.
2. Description of the Related Art
The publication "Ovsepjan G. S., Suvorov A. A. The effect of ultrasonic vibrations of a liquid lubricant and/or coolant on the characteristics of a cutting process. Brief presentation theses at the VIII Pan-soviet scientific and productional conference on electrophysical and electrochemical working methods ELFA-77 (Dec. 13-15, 1977), Leningrad", discloses an apparatus for working of metals by cutting, said apparatus comprising a power supply, a tool, a magnetostriction converter, and a concentrator, inside which is an axial conduit for supplying a liquid lubricant and/or coolant onto the cutting area. When flowing through said conduit, the liquid lubricant and/or coolant is subjected to an ultrasound treatment which improves its lubricating and cooling properties and reduces the degree of plastic strain within the chip-forming area. A defect in this prior known apparatus is that the ultrasound treatment of a liquid lubricant and/or coolant is not sufficiently effective due to small amounts of liquid lubricant and/or coolant subjected to the treatment and due to a short duration of the ultrasound oscillation applied thereto as well as due to the location of a concentrator in the proximity of a surface to be treated, which is why this apparatus can only make use of liquid lubricants and/or coolants at a low viscosity without homogeneous and heterogeneous additives.
In terms of technical significance and achieved result, closest to the apparatus of this invention is what is disclosed in the publication "Hudobin L. V. Lubricants and/or coolants used in grinding. M.,`Mashinostrojenie`, 1971, prototype" as an ultrasound device for cleaning grinding wheels, comprising a concentrator and a magnetostriction converter rigidly secured to a curving corrugated tube. The converter, accompanied by its concentrator, is fitted in cylindrical housing, which is also provided with a pipe and a connector for supplying a liquid lubricant and/or coolant onto the working surface.
When the apparatus is operating, the cylindrical housing is supplied through the connecting pipe with a liquid lubricant and/or coolant, which fills the pipe to the top surface and runs through this pipe and the connector to the end of the corrugated tube and onto the working surface of a grinding wheel. From an ultrasound generator extends a supply to a magnetostriction converter and concurrently the liquid lubricant and/or coolant as well as the corrugated tube are subjected to ultrasound oscillations. By virtue of the wave-like movement of liquid and the cavitation of liquid, the action on the surface of a grinding wheel through the liquid intensifies vigorously, this surface is cleared of metal particles and grinding residues, greasiness is reduced, and working efficiency of the grinding wheel is improved.
A defect in this prior known apparatus is a low efficiency of the ultrasound treatment, which is why it cannot be used with liquid lubricants and/or coolants, which are organic mixture blends and which contain for example asphaltenes--resins which have a lower thermal stability and solubility than aromatic hydrocarbons. This type of liquid lubricants and/or coolants are needed when working metals by cutting, grinding, turning, drilling etc. In addition, when using the prior known apparatus, it is not possible to achieve a necessary stability for water-in-oil emulsions, the decrease of viscosity is slight and so is the increase in the anti-bacterial resistance of a liquid lubricant and/or coolant.